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Diffstat (limited to 'doc/gawk.texi')
| -rw-r--r-- | doc/gawk.texi | 42 |
1 files changed, 39 insertions, 3 deletions
diff --git a/doc/gawk.texi b/doc/gawk.texi index 60fb7944..15b43038 100644 --- a/doc/gawk.texi +++ b/doc/gawk.texi @@ -839,8 +839,8 @@ particular records in a file and perform operations upon them. @command{git} repository. * Future Extensions:: New features that may be implemented one day. -* Implementation Limitations:: Some limitations of the - implementation. +* Implementation Limitations:: Some limitations of the implementation. +* Old Extension Mechansim:: Some compatibility for old extensions. * Extension Design:: Design notes about the extension API. * Old Extension Problems:: Problems with the old mechanism. * Extension New Mechanism Goals:: Goals for the new mechanism. @@ -34084,6 +34084,7 @@ maintainers of @command{gawk}. Everything in it applies specifically to * Additions:: Making Additions To @command{gawk}. * Future Extensions:: New features that may be implemented one day. * Implementation Limitations:: Some limitations of the implementation. +* Old Extension Mechansim:: Some compatibility for old extensions. * Extension Design:: Design notes about the extension API. @end menu @@ -34715,6 +34716,42 @@ different limits. @item Size of a printf string @tab @code{MAX_INT } @end multitable +@node Old Extension Mechansim +@appendixsec Compatibility For Old Extensions + +@ref{Dynamic Extensions}, describes the supported API and mechanisms +for writing extensions for @command{gawk}. This API was introduced +in @strong{FIXME: VERSION}. However, for many years @command{gawk} +provided an extension mechanism that required knowledge of @command{gawk} +internals and that was not as well designed. + +In order to provide a transition period, @command{gawk} version +@strong{FIXME: VERSION} continues to support the original extension mechanism. +This will be true for the life of exactly one major release. This support +will be withdrawn, and removed from the source code, at the next major +release. + +Briefly, original-style extensions should be compiled by including the +@file{awk.h} header file in the extension source code. Additionally, +you must define the identifier @samp{GAWK} when building (use +@samp{-DGAWK} with Unix-style compilers). Otherwise, the definitions +in @file{gawkapi.h} will cause conflicts with those in @file{awk.h} +and your extension will not compile. + +Just as in previous versions, you load an old-style extension with the +@code{extension()} built-in function (which is not otherwise documented). +This function in turn finds and loads the shared object file containing +the extension and calls its @code{dl_load()} C routine. + +Because original-style and new-style extensions use different initialiation +routines (@code{dl_load()} versus @code{dlload()}), they may safely +be installed in the same directory (to be found by @env{AWKLIBPATH}) +without conflict. + +The @command{gawk} development team strongly recommends that you +convert any old extensions that you may have to use the new API +described in @ref{Dynamic Extensions}. + @node Extension Design @appendixsec Extension API Design @@ -34942,7 +34979,6 @@ conflicts. Of course, as of this writing, no decisions have been made with respect to any of the above. - @c ENDOFRANGE impis @c ENDOFRANGE gawii |